The U.N. Security Council voted unanimously Tuesday to extend the authorization of the NATO-led force in Afghanistan, expressing concern at the upsurge in violence and terrorist activity by the Taliban, Al Qaeda and drug traffickers.

Some 20,000 NATO soldiers in the International Security Assistance Force and a similar number of U.S. forces in Afghanistan are facing an emboldened insurgency led by the country's former Taliban rulers that has demonstrated the fragility of Afghanistan's fledgling Western-style democracy.

CountryWatch: Afghanistan

The violence, centered in the Taliban heartland in southern Afghanistan, is the deadliest since a U.S.-led invasion toppled the Taliban's hard-line regime after Sept. 11, 2001, for harboring Al Qaeda leader Usama bin Laden.

The Security Council resolution adopted Tuesday extends the authorization for the NATO-led force known as ISAF for 12 months after the current authorization expires on Oct. 13. The council acted a month early so Germany and other countries can get approval from their parliaments for the continued deployment of their troops, council diplomats said.

The 15-nation council expressed "concern about the security situation in Afghanistan, in particular the increased violent and terrorist activity by the Taliban, Al Qaeda, illegally armed groups and those involved in the narcotics trade, which has resulted in increased Afghan civilian casualties."

Afghanistan's U.N. Ambassador Ravan Farhadi welcomed the decision but called for quick action in expanding the force. "What Afghanistan is expecting is the broadening of the role of ISAF -- that's really the next step," he said.

Some 8,000 NATO troops, mainly from Britain, Canada and the Netherlands, relieved U.S.-led soldiers in southern Afghanistan on July 31. Fighting since then has left at least 35 NATO troops and over 500 militants dead.

NATO officials have been holding talks aimed at pushing member states to commit more troops to bolster the mission in southern Afghanistan amid stiff resistance from Taliban and other insurgents.

Russia's deputy U.N. ambassador Konstantin Dolgov said ISAF is "playing a very important stabilizing role in Afghanistan under the mandate from the Security Council."

He told The Associated Press that ISAF already is broadening its area of operation and by the end of the year its troops have to be deployed in eastern Afghanistan.

In addition to tackling the "very serious threat coming from the remnants of the Taliban and Al Qaeda," Dolgov called for progress on political reforms and reconstruction, which the U.N. is helping to coordinate.

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